Assictor to westerni electric



J. C. FIELD.

SIGNALING SYSTEM.

APPLICATION man APR-2. me.

Patented Dec. 9,1919.

//7|/en for: Joseph C fi'e/d nnrrnn er JOSEPH C. FIELD, OF ORANGE, NEW JERSEY, ASSIGNOR 'lO WESTERN ELECTRIC COMPANY, INCORPORATED, OF NElV YORK, N. Y., A CORPORATION OF NEW" YORK.

SIGNALING SYSTEM.

Specification of Letters Patent.

Patented Dec. 9, that).

To all whom, it may concern:

Be it known that I, JOSEPH C. FIELD, a citizen of the United States residing at Grange, in the county of Essex, State of New Jersey, have invented certain new and useful Improvements in Signaling Systems, of which the following is a full, clear, conelse, and exact description.

This invention relates to signaling systems, and more particularly to selective sig naling systems in which a plurality of way stations connected with a single line circuit are each provided with a selectively operated signal controlling device.

The object of this invention in general is to provide an improved organization of apparatus and circuits whereby any station on a line may, without assistance, be called from any other station on the same line without operating the signals at any of the other stations on the line, and to provide improved means for receiving time signals at the. various stations.

In accordance with one feature of this invention, the selectively operated'devires are each siinplexed to ground. from the 1niddle point or an inductive bridge and are operated over the simplex circuit from a common source of current, the connection of which with the simplex circuit is controlled by a relay energized over a metallic circuit controlled by keys provided at the stations.

In accordance with another feature of this inventioin there provided at each station a signaling device controlled by the selectively operated device thereat and operativel y connected with the line wires upon the operation of the usual repeating relay of an associated time circuit for simultaneously receiving time signals at all stations connected with the line.

The drawing is a diagram of circuits and apparatus illustrating this invention and in which in Figure 1 is shown one form of sending circuit. while in Fig. 2, another Form shown.

In Fig. 1 of the drawing 5 and 6 desigiii-rte a pair of line wires with which are associated a plurality of way-stations, only two of which, A and B, are shown. At each of the way-stations there is a selectively operated signal controlling device, each comprising. in general a. polarized operating magnet 7, a step-by-step element 8 carrying a contact arm 9, and stationary contact ele ments l0 and 11. The step-bystep element 8 is mounted upon a shaft and is held in the position shown by means of a coiled spring 56, one end or which is secured to the shaft 55 and the other end of which is held in fixed position. In order that the contact arrying element 8 may be advanced step by step against the action of the coiled spring56,there is mounted upon the shaft 55 a ratchet wheel 53 adapted to he engaged by a stepping pawl 13 and a holding pawl. 54. The stepping pawl 13 is mounted upon the outer end of a pivoted rocker arm 50 While the holding pawl 54 is pivotally mounted and controlled by the rocker arm 50. The cent ally pivoted armature 12 carries an S shaped arm 49 upon which are mounted pins 51 and 52-, so positioned that they impinge upon opposite sides of the rocker arm 50, whereby the stepping pawl 13 is caused to engage the ratchet wheel 53 upon each energization of the selector magnet 7. The holding pawl 5% is adapted to maintain the ratchet wheel and contact-carrying element 8 in advanced position during a reversal. of current through the windings oi the selector magnet. Upon the cessation of the last stepping impulse of the series which advance the element 8 into position where the contact arm 9 carried thereby enga es the stationary contact 10,, the pivoted a ture 12 returns to its normal. positioiu who. eupon the spoon-ended spring l-t controlled by the rocker arm 50, engages the holding pin 15 carried by the element 8. holding the element in contact-engaging position against the action of the coiled spring 56. The element 8 is, therefore, held in contact-engaging position until further impul: are transmitted through the winding of the lector magnet to advance the element 8 to a position where upon the cessation of the last of these impulses the holding spring ll will not engage the holding pin carried by the element 8. The coiled spring there upon returns the element 8 to normal position. If the number of im 'iulscs t mitted through the winding of the selector magnet 7 is suflieient to advance the element 8 into position where the contact en gages the stationary contact 11, then upon the cessation of the last of the steppii'ig' im pulses, the spoon-ended holding spring 1 1: engages the holding pin 16 carried by the element 8 and holds the element in contactengaging position against the action 01 the coiled spring 56. To restore the selector to normal position further impulses are transmitted through the selector magnet 7 to move the element 8 into position where upon the cessation of the last of these impulses holding spring 14 will not engage the holding pin. The coiled spring 56 then restores the element 8 to normal position.

The selectively operated signaling device illustrated in the drawing which is of the type disclosed in my co-pending application, Serial No. 98,384., filed May 18, 1916, is pro vided with one or more intermediate holding pins mounted on the element 8 which are variously positioned in different selectors. whereby for a predetermined code or combination of impulses transmitted, the station contact, namely contact 10, of but one-way station connected with the line will be engaged by its associated contact arm 9. In fact, the contact arm at but one of its stations will be advanced as far as its station contact 10. It will be understood that the same number of impulses are transmitted for selecting the various way-stations, the grouping of these impulses being difl erent for the different stations. To advance he contact arms 9 of all stations into engagement with the stationary contacts 11 one continuous group of impulses is transmitted over the line circuit. The number of impulses of this group is, however, greater than the combined number of impulses of the groups comprising the code or combination of impulses required to selectively call the same stations.

Connected to the line wires 5 and 6 at each of the waystations is an inductive bridge comprising two impedance coils 20 and 21 and two condensers 22 and 23, the impedance coils and condensers of each bridge being included in serial. relation with respect to each other. One terminal of the magnets 7 at each station is connected with ground and the other with the inductive bridge at a point between the condensers 22 V and 23. At each way-station 1s a key 2t employed for calling any other station. The closure of the contact of the key 2-1 short-circuits the condensers 22 and 23, thereby establishing a direct current bridge across the line wires 5 and 6.

At the way-station A there is a sending battery 30 connected through the norn'ially closed contacts of an impulse or pole changing relay 31 with the middle contacts of a double pole double throw switch 32. The voltage of the sending battery 30 varies with the length of the line and may be upward of 300 volts. When the switch 32 is thrown to the left, the upper terminal of? battery 30 is then connected to the middle point of the windings of relay 31 and the lower terminal is connected with ground. When the switch 32 is thrown to the right, the terminals of the battery 80 are con nected with the line wires 5 and 6 through retardation coils 33 and 3%, across the junction points of which are connected a condenser 35 and a. resistance 36, all of which cooperate to smooth out the impulses of current transmitted to the line wires to prevent interference with the telephone apparatus which may be connected with the line wires. The outer terminals of the windings of the relay 31 are connected with the middle contacts of a double pole double throw switch 37, a battery 38 being in the lead connected with the upper terminal. W hen the switch 37 is thrown to the left, the outer terminals of the windings of relay 31 are connected with the line wires 5 and 6, am when thrown to the right, the outer terminals of the windings of the relay 31 are connected with the normally open contacts of a repeating relay 39 in a telegraph circuit. The voltage of battery 38 will vary with the length of the line, and for the longest line will probably be not over fifty volts. hen the sending apparatus at station A is connected for calling between stations the two switches 32 and 37 are thrown to the left and the windings of the relay 31 and the battery 38 are connected in series across the line wires 5 and 6, while the battery 30 is connected between ground and the middle point of the windings ol relay 31, so that battery may be fed through the two windings in parallel and then over the line wires 5 and 6 in parallel. lVhen the sending apparatus is connected for receiving time signals, the switches 32 and 37 are thrown to the right and battery 30 is connected in bridge of the line wires and 0 while the impulse relay 31 is controlled by the repeating relay 39.

At station A, the polarized bell 18 is normally short-circuited by the closed contact of a relay 19 included in a local circuit which is closed when contact arm 9 of the selecti vely operated signal control device thereat engages the stationary contact 11. When relay 1.9 operates, opening the short circuit, the bell 18 is included in bridge of the line wires.

The polarized bell of station E is bridged across the line wires 5 and '6 when contact arm 9 of the selectively operated signal control device thereat engages the stationary contact 11.

The sending circuit shown in 2 diti ers from that shown in Fig. 1 merely in that two relays are employed to control the connection of battery 80 with the line wires, instead of one relay, as in Fig. 1. Relay 41 is controlled over the line wires when the allel, over the line wires retardation cells 20 and operates.

' arm 9 switch 37 is thrown to the left, and by the repeating relay 39 when this switch is thrown to the right. Relay 41 controls a pole changing relay 42, which, in operating, reverses the connections of the sending battery 30 to the line wires 5 and 6.

Vi hen the system is in condition for calling between stations, the arms of switches 32 and 37 are in position to engage their respective left-hand contacts. Pole changing relay 31 may now be controlled over the metallic line circuit and the sending battery 30 is connected with the simplex circuit. The operator at any way-station, desiring to call another way-station on the same line circuit, may actuate the key 2-1 thereof to make and break contact to give the correct combination of impulses to operate the selector at the station called. When the contact of key 24 is closed, pole changing relay 31 operates over a circuit from one pole of battery 38 through the upper and lower windings of relay 31, lower arm of the switch 37, retardation coils 34, line wire 6, retardation coil 21, contact of key 24;, retardation coil 20, line wire 5, retardation coils 33, upper arm of switch 37 and to the other pole of battery 38. Pole changing relay 31, in operating, reverses the connections of battery 30 to the line wires and ground, thereby causing the energization of ma nets 7 of the selectors over a circuit which may be traced from ground through the lower arm of switch 32, lower alternate contact of relay 31, sending battery 30, upper alternate contact of relay 31, upper arm of switch 32, both windings of relay 31 in parallel, then through the upper and lower arms oi switch 37 in par 5 and Sin parallel, 21 in parallel, condensers fiend 23 in parallel, and the windings of electromagnets 7 in series to ground.

When the contact of key 24: is opened the I connections of battery 30 to the simplex circuit are reversed, causing the reenergization of the magnets 7. The closing. and opening of the contact of key t causes a flow of current impulses through the windings of the magnets 7 alternately in opposite directions to advance the step-by-step elements 8 until the station contacts 9 and 1t) ot the desired station are closed. Upon the engagement of contact arm 9 with the stationary contact 10 at the desired. waystation, the local. vibrating bell 17 thercat These contacts are held in en gagement as long as the spoon-shaped end of the holding spring l t rests against the pin 15, the position assumed upon the cessation. of the last impulse of current over the simplex circuit. During the operation of hell 17, due to the closure of its local circuit upon the engagement of the contact with the stationary contact 10, the

or answer-back signal indication the line circuit at station A.

When it is desired to condition all of the way-stations for the simultaneous reception of time signals, the operator of way-station A may, by actuating the key 2 1, impress upon the simplex circuit, the number of im-. pulses required to cause the contact arms 9 at all stations to engage the stationary c011- tacts 11, when the pins 16 in all contactcarrying elements 8 will be engaged by the holding springs 14:, thereby maintaining all selectors in position so that the bells 18 may receive time signals simultaneously. The operator at station A, after conditioning the apparatus at the way-stations, may change the position of the swtiches 32 and 37 so the arms thereof engage the right instead of the left-hand contacts. Pole changing relay 31. is now controlled by the repeating relay 39 and the sending battery 30 is connected in bridge of the line wires 5 and 6. At station A, when the contact of arm 9 engages the stationary contact 11, relay 19 is energized to remove a normal short circuit from about the single stroke bell 18, thereby including this bell in a bridge of the line wires 5 and 6. At station B, the engagement of the contact of the arm 9 with the stationary contact 11 connects the bell 18 in a bridge of the line wires 5 which includes tact arm 9, step-loy-step holding spring 1 1 and condenser 13. When the time signals are being received, repeating relay 39 responds to each impulse trans mitted over the circuit in which it is connected, When relay 39 responds, pole changing relay 31 is energized over a circuit from battery 38 through two windings of pole changing relay 31 in series, lower arm of switch 37, contact of repeating relay 39, upper arm of switch 37 back to battery 38.

element 8, pin 16,

.Pole changing relay 31, in operating, re-

verses the connections of the sending battery 30 to the line wires 5 and 6, thereby causing the operation of the bells 18 which are bridged across the line wires 5 and 6. It is to be noted that the bells 18 operate over a metallic circuit and that since the selector magnets are connected in a simplex circuit, they will not be energized by impulses transmitted over the metallic circuit when time signals are being received. The bells 18 operate upon each closure of the contact of the repeating relay 39 in response to im pulses over the circuit in which it is conthe contact 11, connected. After the time signals have been reeeived, the operator at way-station A may restore the switches 32 and 37 to position to engage the left instead of the right-hand contacts and may then actuate the key 2 L thereat a sufficient number of times to cause the holding springs 1a to disengage the pins 16, whereupon all of the step-by-step elements 8 are returned to normal vposition.

l hat is claimed is:

1. In a signaling system, in combination,

a pair of metallic line wires having a plurality of stations connected therewith, a source of current, an electromagnetic switching device controlling the connection of the source of current with the line wires, a signal-controlling device at each station con nected between the line wires and ground and responsive to current from said source transmitted over the line wires in parallel, a. condenser at each station connected in bridge with the line wires and between the line wires and the signal-controlling device thereat, an energizing circuit for the electromagnetic switching device, and akey at each station for short-circuiting the condenser thereat to control the energizing cir cuit.

2. In a signaling system, in combination, a pair of metallic line wires having a plurality of stations connected therewith, a pair of condensers at each station connected in bridge of the line wires, selective signaling means at each station. connected with ground and with the line wires tirough the condensers, impulsesending means for operating the selective signaling means over a circuit including the two line wires in parallel, and means at each station for short-circuiting the condensers thereat for controlling the operation of the impulse-sending means.

3. In a signaling system, in combination, a pair of metallic line wires having a plurality of stations connected therewith, a selector at each station bridged between the line wires and ground and responsive to alternating current impulses, a pole changing relay, a source of current having one pole connected with both line wires through contacts controlled by the pole changing relay, means at each station for bridging the line wires, and an energizing circuit for the pole changing relay completed when the line wires are bridged for reversing the connections of the source of current to the line wires.

*1. In a signaling system, in combination, a pair of metallic line wires having a plurality of stations connected thereith, selective signaling means at each station bridged between the line wires and ground and re sponsive to alternating current impulses, a pole-changing relay, a source of current having one pole connected with both line wires through contacts controlled by the polechanging relay, an energizing circuit for the pole-changing relay, and means at each station for controlling the energizing circuit.

5. In a signaling system, in combination, a pair of metallic line wires having a plu rality oi stations connected therewith, a source of current, a switch ateach station, a double wound relay controlling the connection of the source of current with the line wires, an operating circuit for the relay including the two windings connected in series completed by the actuation of one of the switches, and a selectively operated signal controlling device at each station responsive to current from said source transmitted through the windings of the relay and over the line wires in parallel.

6. In a signaling system, in combination,

metallic line wires having a plurality of stations connected therewith, a source of current, a switch at each station, a relay controlling the connection of the source of current with the line wires, an operating circuit for the relay including the winding and the line wires connected in series and completed by the actuation of one of the switches, and a selectively operated signal controlling device at each station responsive to current from said source transmitted through the winding of the relay and over the line wires in parallel.

7 In a signaling system, in combination, a pair out metallic line wires having a plurality of stations connected therewith, a source of current, switching means having two operative positions, an electromagnetic switching device controlling the connection of the source or current with the line wires, a key at each station controlling the energization of the electromagnetic switching de vice, signal controlling devices at the stations responsive to current from said source transmitted over the line wires in parallel when the switching means is in one operative position, a relay controlling the operation of the electromagnetic switching device when the switching means is in its other operative position, and signaling devices at the stations responsive to current from said a pair of source transmitted over the line wires in series when the relay controls the electromagnetic switching device.

8. In a signaling system, in combination, a pair of metallic line wires having a plurality of stations connected therewith, a source or current, switching means having two op erative positions, an electromagnetic switching device controlling the connection of the source or current with the line wires in parallel when the switching means is in one op erative position and with the line wires in series when the switching means is in its other operative position, means controlling the energization of the electromagnetic switching device, signaling devices at the erative positions, an electromagnetic switching ice controlllng the connection of the source oi current with the line wires in parallel when the switching means is in one operative position and with the line wires in series when the s*- itching means is in its other operative :QCSltl011,1118ztllS at each station controlling the energization of the electromagnetic switching device, signaling devices at the stations responsive when current is transmitted over the line wires in parallel by the actuation of the controlling means, other means at one station controlling the ener ization of the electromagnetic switch-- ing device, and signaling devices at the stations responsive to current transmitted over he line wires in series by the actuation of he last mentioned controlling means.

10. in signaling systen1,in combination, a pair ofmetallic line wires having a plurality of stations connected therewith, a source of c rrent, sv telling 111684118 having two operative positions, an impulse relay controlling the counection'otf the source current with the line wires in parallel when the switching means is in one operative position and with the line wires iii-series when the switching means is in its other operative position, a key at each station, an energizing circuit for the impulse relay completed over the line wires in series by the actuation of any key, signaling devices at the stations responsive when current is transmitted over the line wires in parallel by the actuation of any key, an electromagnetic relay at one station controlling the energization of the impulse relay, and signaling devices at the stations responsive to current transmitted over the line wires in series by the operation or? the electromagnetic relay.

11. In a signaling system, in combination,

a pair of metallic line wires having a plurality of stations connected therewith, a source of current, a selective signaling device at each station bridged between the line wires and g *ound, impulse sending means for operati the selective signaling devices over a circuit including the two line wires in parallel, a movable contact member for each selective signaling device, and signaling devices at each station connected in bridge of the line wires by the advancement of the movable contact members to a predetermined position and responsive to current from said source thereafter transmitted over the line wires in series.

12. In signaling system, in combination, a pair of metallic line wires having a plurality oi stations connected therewith, a source of current, selective signaling devices at each station bridged between the line wires and ground, switching means having two operative positions, impulse sending means for operating the selective signaling devices over a circuit including the two-line wires in parallel when the switching means is in one operative position, a movable contact member for each selective signaling device, and a si naling device at each station connected in bridge of the line wires by the advancement of the movable contact members to the predetermined position and responsive to current from said source thereafter transmitted over the line wires in series when the switching means is in its other operative position.

In witness whereof I hereunto subscribe my name this 27th day of March, A. D., 1

JOSEPH o. since. 

